In a mixed reality environment, a system often displays virtual graphical information, but currently, fused display of virtual graphic information and reality information is not yet implemented desirably. For example, when a user gazes somewhere (an actual object or a virtual graph), due to an incorrect depth or location of a virtual graph, the user fails to clearly see virtual graphic information needing to be seen; or, when a user gazes somewhere, virtual graphic information located at other depths and locations is also clearly displayed, and no proper bokeh effect is produced, which affects a real sense of immersion of the user. For example, currently, Google glasses can only display virtual content on a virtual screen at a specific distance, and as a result, the content cannot be well fused with the reality; therefore, the virtual screen can only be placed in angled upper front of the glasses, and a user needs to deliberately look upwards to view virtual graphic information, which seriously affects visual experience of the user. However, in a mixed reality system with stereoscopic visions for both eyes, information of stereoscopic depth is further added, and consequently, it is harder to reconcile a virtual system and a reality system, and setting the location of the virtual graphic information incorrectly further causes trouble such as diminution of vision, dizziness, and headache to a user.